Re: Return value of pg_promote()

On Tue, 2023-06-06 at 16:35 +0530, Ashutosh Sharma wrote:
> At present, pg_promote() returns true to the caller on successful
> promotion of standby, however it returns false in multiple scenarios
> which includes:
>
> 1) The SIGUSR1 signal could not be sent to the postmaster process.
> 2) The postmaster died during standby promotion.
> 3) Standby couldn't be promoted within the specified wait time.
>
> For an application calling this function, if pg_promote returns false,
> it is hard to interpret the reason behind it. So I think we should
> *only* allow pg_promote to return false when the server could not be
> promoted in the given wait time and in other scenarios it should just
> throw an error (FATAL, ERROR ... depending on the type of failure that
> occurred). Please let me know your thoughts on this change. thanks.!

As the original author, I'd say that that sounds reasonable, particularly
in case #1. If the postmaster dies, we are going to die too, so it
probably doesn't matter much. But I think an error is certainly also
correct in that case.

Yours,
Laurenz Albe